Double print preventing shield in web printing machines



W. J. STARK Aug. 4, 1954 DOUBLE PRINT PREVENTING SHIELD IN WEB PRINTING MACHINES Filed Sept. 27, 1962 INVENTOR WALTER ,1. STARK BY M fl HIS ATTORNEYS United States Patent 3,143,063 DOUBLE PRINT PREVENTING SHIELD IN WEB PRINTDIG MACHINES Walter J. Stark, Dayton, Ohio, assignor to The National Cash Register Company, Dayton, Ohio, a corporation of Maryland Filed Sept. 27, 1962, Ser. No. 226,668 3 Claims. (Cl. 10193) This invention relates to printing mechanism, and more particularly relates to printing mechanism having a device for preventing double printing on record material where the record material is doubled over in passing between the hammer and the type surface of the printing mechanism.

In certain printing devices, the arrangement of parts is such that it is necessary for the record material being printed upon to follow a doubled-over or looped path which provides two webs of material between the type surface and the printing hammer. This may be required for example, where the design of the printing mechanism dictates that the supply roll and take-up means of the record material must be positioned adjacent each other, for easy insertion and withdrawal of the record material, or for some other reason, and on the same side of the hammer and type surface elements.

No problem arises in such a structure when only a single sheet of record material is to be printed upon, using a conventional ink ribbon. However where a single sheet of a special type of record material is used in which the marking material is contained in a coating or impregnation of the record material for release merely by the application of pressure without need for a ribbon; or where multiple sheets of record material are necessary to provide duplicate records, the second and following sheets being marked upon by a carbon-backed first sheet, by an interleaved carbon sheet, or by a carbonless transfer system, then some means must be provided to prevent the simultaneous printing on both webs of the loop of the record material.

Such means are provided by the present invention, in the form of a shield interposed between the two webs of record material and capable of transmitting the force of the printing hammer through one web of the record material without causing printing thereon, to effect printing on the other web.

It is accordingly an object of the present invention to provide an improved printing mechanism.

Another object is to provide means by which two webs of record material may be interposed between the hammer and type surface of a printing mechanism so that printing takes place on only one of the webs.

A further object is to provide, in a printing mechanism, a novel shield which prevents undesired printing on one of two webs of record material.

With these and other objects, which will become apparent from the following description, in view, the invention includes certain novel features of construction and combinations of parts, a preferred form or embodiment of which is hereinafter described with reference to the drawings which accompany and form a part of this specification.

Of said drawings:

FIG. 1 is a detail view showing the novel printing means of the present invention.

FIG. 2 is an enlarged partial detail view, showing in greater detail the relationship of the type wheel, shield, hammer and ribbon with a looped double-sheet web of record material.

As shown in FIG. 1, the printing mechanism of the present invention includes at least one type wheel 12 having a plurality of type characters 14 distributed about the periphery thereof. The type wheel 12 is mounted on a shaft 16, and in the illustrated embodiment is positioned from appropriate control mechanism through an internal gear drive unit 18 of the type shown and described in the United States patent to Walter J. Kreider, No. 1,693,279. Of course it will be realized that any suitable means could be used to position the wheel 12 in accordance with the information to be printed.

A hammer 20 is provided for cooperating with the type wheel 14 to take an impression therefrom, and is selected and operated by mechanism including the link 22, which mechanism may be of the type shown and described in the United States Patent to Konrad Rauch et al., No. 2,947,- 475.

Situated between the type wheel 12 and the hammer 20 is a shield 24 comprising a pad 26 of resilient material, such as rubber of medium hardness, fixed to a plate 28, also of resilient material, such as spring steel. The plate 28 is secured to a bracket 30 which forms part of the framework of the printing mechanism. The pad 26 and the plate 28 are of sufiicient width to extend completely across the face of the hammer 20, and are of thickness appropriate to the character and thickness of the record material and the force with which the hammer is operated. For example, in the illustrated embodiment, it has been found that using a double-sheet Web of conventional journal paper of the carbonless transfer system type as the record material, a thickness of 0.010 inch of the plate 28, and a thickness of 0.030 inch of the pad 26, produces satisfactory printing on both sheets of the web. Actually, the mechanism would function without the pad 26, but it is provided to prevent excessive mutilation of the type ribbon, which would otherwise take place.

The record material 32 to be printed upon is shown generally in FIG. 1, and may include two sheets 34 and 36, as shown in FIG. 2, to enable a duplicate record to be produced simultaneously with the original. With either a single or multiple-sheet record material, an ink ribbon 38 of conventional design may be provided for inking of the type characters for printing on the record material. Alternatively, the single sheet, or the top sheet of the multiple-sheet web, if used, of the record material may be of a type in which all of the necessary ingredients for producing a legible mark are contained in the sheet itself, either by means of a coating, or by impregnation of the sheet, so that pressure of the type character on the sheet is all that is required to produce the desired marking. In the case of a multiple-sheet web of record material, such as the two sheets 34 and 36, the duplicate marking on the second sheet may be accomplished by means of a carbon backing on the first sheet, by means of an interleaved carbon sheet, or by a carbonless transfer system, as previously stated.

The web of record material is fed into the printing mechanism from a supply source (not shown) over the bracket 30, and between the ribbon 38 (if one is used) and the pad 26 of the shield 24. The web is then reversed in direction around a first idler roll 40 and proceeds over second and third idler rolls 42 and 44, and through a driving means consisting of a drive roll 46 and a tension roll 48. The record material 32 may then be directed to the exterior of the printing mechanism, or to a take-up roll, or otherwise disposed of as desired.

Operation of the mechanism of the present invention is believed to be clear from the drawings and the foregoing description, but will be briefly described. With the record material 32 looped through the printing mechanism as shown in FIGS. 1 and 2, operation of the hammer 20 causes the lower web of record material to be pressed between the hammer 20 and the lower surface of the shield 24, while the upper web of record material and the ribbon 38 are compressed between the upper surface of the pad 26 of the shield 24 and the selected type character 14- of the type wheel 12. The pressure on the lower web of the record material 32 is evenly distributed over the entire area of the face of the hammer 20 by the shield 24, and therefore no print is produced on this lower web, although a slight smudging in that area may result.

The force of the operation of the hammer 20 is transmitted by the shield 24 to press the upper web of the record material 32 and the ribbon 38 against the selected type character 14. This force is concentrated in the relatively small area of the lines making up the configuration of the selected type character, and is thus sufiicient to produce a mark corresponding to the character on all sheets of the upper web of the record material 32. It will, of course, be noted that if the shield 24 were not interposed between the upper and lower webs of the record material, the character would be reproduced on the lower web of the record material, as well as on the upper web, thus greatly reducing the legibility of the record being maintained on the record material.

While the form of mechanism shown and described herein is admirably adapted to fulfill the objects primarily stated, it is to be understood that it is not intended to confine the invention to the one form or embodiment disclosed herein, for it is susceptible of embodiment in various other forms, Within the scope of the appended claims.

What is claimed is:

1. Printing mechanism comprising, in combination,

a type surface containing type characters for enabling printing to be produced on record material; control means for setting the type surface to bring the desired type characters into printing position; hammer means for moving the record material with respect to the type surface to produce printing on the record material; operating means to drive the hammer means; guide means to guide the record material in a looped path between the type surface and the hammer means so that two webs of said material are presented therebetween; and

resilient shielding means including a spring member and a resilient pad fixed to said spring member interposed between the two webs of record material and capable of transmitting the force of the hammer means over a relatively large area through a first one of the webs between the hammer means and the 4 shielding means to a relatively small area corresponding to the configuration of the type character on a second one of the webs adjacent the type surface so.

that printing takes place only on the second web and not on the first web.

2. Printing mechanism comprising, in combination,

a type surface containing type characters for enabling printing to be produced on record material;

control means for setting the type surface to bring the desired type characters into printing position;

hammer means for moving the record material to produce printing on the record material from the type surface;

operating means to drive the hammer means;

guide means to guide the record material in a looped path between the type surface and the hammer means so that two webs of said material are presented therebetween; and

resilient shielding means mounted in fixed relation to the guide means and including a spring member interposed between the two webs of record material and capable of transmitting the force of the hammer means to the web adjacent the type surface so that printing takes place only on that web and not on the other web.

3. Printing mechanism comprising, in combination,

a type surface containing type characters positionable for enabling printing to be produced on record material;

hammer means capable of being operated for moving the record material to produce printing on the record material from the type surface;

guide means to guide the record material in a looped path between the type surface and the hammer means so that two webs of said material are presented therebetween; and

a spring member interposed between the two Webs of record material and capable of transmitting the force of the hammer means to the Web adjacent the type surface so that printing takes place only on that web and not on the other web.

References Cited in the file of this patent UNITED STATES PATENTS 833,029 Dement Oct. 9, 1906 1,953,316 Stark Apr. 3, 1934 2,849,096 Markes Aug. 26, 1958 

3. PRINTING MECHANISM COMPRISING, IN COMBINATION, A TYPE SURFACE CONTAINING TYPE CHARACTERS POSITIONABLE FOR ENABLING PRINTING TO BE PRODUCED ON RECORD MATERIAL; HAMMER MEANS CAPABLE OF BEING OPERATED FOR MOVING THE RECORD MATERIAL TO PRODUCE PRINTING ON THE RECORD MATERIAL FROM THE TYPE SURFACE; GUIDE MEANS TO GUIDE THE RECORD MATERIAL IN A LOOPED PATH BETWEEN THE TYPE SURFACE AND THE HAMMER MEANS SO THAT TWO WEBS OF SAID MATERIAL ARE PRESENTED THEREBETWEEN; AND A SPRING MEMBER INTERPOSED BETWEEN THE TWO WEBS OF RECORD MATERIAL AND CAPABLE OF TRANSMITTING THE FORCE OF THE HAMMER MEANS TO THE WEB ADJACENT THE TYPE SURFACE SO THAT PRINTING TAKES PLACE ONLY ON THAT WEB AND NOT ON THE OTHER WEB. 